Project description:The exon junction complex (EJC) is composed of three core proteins Rbm8a, Magoh and Eif4a3 and is thought to play a role in several post-transcriptional processes. In this study we focus on understanding the role of EJC in zebrafish development. We identified transcriptome-wide binding sites of EJC in zebrafish via RNA:protein immunoprecipitation followed by deep sequencing (RIP-Seq). We find that, as in human cells, zebrafish EJC is deposited about 24 nts upstream of exon-exon junctions. We also identify transcripts regulated by Rbm8a and Magoh in zebrafish embryos using whole embryo RNA-seq from rbm8a mutant, magoh mutant and wild-type sibling embryos. This study shows that nonsense mediated mRNA decay is dysregulated in zebrafish EJC mutants.
Project description:Purpose: Construction of 3D zebrafish spatial transcriptomics data for studying the establishment of AP axis. Methods: We performed serial bulk RNA-seq data of zebrafish embryo at three development points. Using the published spatial transcriptomics data as references, we implemented Palette to infer spatial gene expression from bulk RNA-seq data and constructed 3D embryonic spatial transcriptomics. The constructed 3D transcriptomics data was then projected on zebrafish embryo images with 3D coordinates, establishing a spatial gene expression atlas named Danio rerio Asymmetrical Maps (DreAM). Results: DreAM provides a powerful platform for visualizing gene expression patterns on zebrafish morphology and investigating spatial cell-cell interactions. Conclusions: Our work used DreAM to explore the establishment of anteroposterior (AP) axis, and identified multiple morphogen gradients that played essential roles in determining cell AP positions. Finally, we difined a hox score, and comprehensively demonstrated the spatial collinearity of Hox genes at single-cell resolution during development.